Remote sensing of ocean currents using a multifrequency microwave radar

Abstract

A remote sensing system for measuring ocean surface currents is presented in this thesis. Included are a review of the Stepped Frequency Delta K (SFDK) radar system hardware, a description of the system performance, experimental results of ocean current measurements, and comparisons of the measurements with a conventional current probe and a wind driven current model. Important features of this radar system are (1) its capability to perform real time processing of the collected data and (2) its frequency agility, which provides significant improvement of the system's signal-to-clutter ratio. The real time processing capabilities were essential to the collection and monitoring of the ocean currents for long periods of time that is necessary to understand and interpret the results. The SFDK radar participated in two month long experiments. During the first experiment at N. Truro, MA, the SFDK radar demonstrated its ability to make precise phase velocity measurements over long periods of time. During the second experiment on the Chesapeake Light Tower, the radar was able to sense both tidal and wind driven current components. Comparison of radar data and in situ measurements during the CLT experiment shows that the instrument possesses a unique capability to measure near surface currents--not possible with in situ probes. ^